Welcome to NiTM


It Helpdesk System Since the use of a proprietary protocol would be limited to those with permission to use it, protocols are almost always eventually standardized. Although not always the case, protocols that are not standardized tend to die out from lack of use. In fact, international standards are often created to ensure that the protocols are universally compatible. As an example, HTTP, HyperText Transfer Protocol, guides communication between Web

It Helpdesk System servers and Web browsers on the Internet. The movement of data through the Internet is controlled by a suite of protocols called TCP/IP (Transmission Control Protocol/Internet Protocol). Storage devices communicate with a computer using a protocol called SATA. There are thousands of such protocols.

It Helpdesk System New protocols and other standards are proposed and created and standardized as the need arises. XML, RSS, and SIP are all examples of protocols developed recently to meet new demands. Satellite telecasting, near-universal telephone communication, wireless communications, and the Internet all demonstrate powerful and useful technologies made possible by protocols and standards. Indeed, the Internet is a measure of the success to which protocols that govern intercommunication between computer hardware and software have been standardized throughout the world. Discussions of various protocols and standards will occur regularly throughout this book.

It Helpdesk System The focus of this book is upon the architecture and organization of computers, computer systems, and computer-based IT systems. Technically, there is a slight difference in definition between the terms ‘‘computer architecture’’ and ‘‘computer organization.’’ In this book we will usually not attempt to differentiate these terms and will use them interchangeably.

It Helpdesk System In this book we will be concerned with all four components of computer systems: hardware, software, data, and interconnectivity, and with the interactions between each component. We will also look initially at the larger picture: the organization of computer systems as components, themselves, to form enterprise IT systems. Chapter 2 of this first part is concerned with the system as a whole. The remainder of this book is divided into four additional parts, consisting of discussions of number systems and the representation of data in the computer, the hardware that makes up the computer, the software that the computer uses, and the networks that interconnect computers.

It Helpdesk System Our first step will be to examine the concept of systems in general. We will look at the characteristics and qualities that define a system. We will then use that basic understanding to look at the characteristics of computer-based IT systems and show how the various elements and requirements of computer systems fit into the system concept. Part 1 illustrates fundamental IT architecture concepts with several examples of IT system architectures.

It Helpdesk System In Part 2, we will look at the different forms the input data may take, and we will consider the translation processes required to convert data into forms that the computer hardware and software can process. You will see how the various data types that are familiar to you from programming languages are stored and manipulated inside the computer. You’ll learn the many different ways in which math calculations can be performed, and the advantages and disadvantages of each. You will see the difference between a number and the alphanumeric representation of a number, and understand why that difference can be critical in whether a program works or not. You It Helpdesk System  will be able to relate the size of a word processing text to the storage capability of the computer’s disk

It Helpdesk System  In Part 3, we will take a detailed look at the various components of the hardware and how they fit together. You will learn how the CPU works, how different I/O devices work, and even how text and graphics manage to appear, seemingly by magic, on the display

It Helpdesk System  screen. You will learn what makes some computers faster and more powerful than others, and what that means. You will learn about different ways of connecting I/O devices to the computer and see why you get a fast response from some devices, a slow response from others. You’ll learn the difference between a serial port, a USB port, and a parallel port. We’ll even explain the difference between PCI and PCI Express buses.

It Helpdesk System Most important, you will have the opportunity to see what a simple, program-obedient machine the computer really is. You will learn about the limitations of a computer. We all tend to think of the computer as a resource of infinite capacity, speed, and perhaps even intelligence, but of course that’s not true. We will consider how these limitations affect your work as a user, and as a means of specifying a system that will your meet your needs and requirements.

It Helpdesk System Part 4 will provide a careful introduction to the foundational principles of communication and networking. We will consider the basic communication technologies, networking hardware, software, channels and channel media, protocols, and methodologies that are required to support communication between computer systems in an IT system environment.

It Helpdesk System In the final part, we will consider the software that is used to control the computer’s basic processing capabilities. Although computer software falls into two categories, operating system software and application software, we will focus exclusively on the system software. We will be concerned with control and efficient use of the computer hardware, fair and effective allocation of computer resources to different programs, security, storage management and file system structure, system administration, security, user interfaces, and more.